Re: NEW(er) heads vs OLD heads

my 48 has a crack like that too, po brazed it and havnt had any problems with it.

Re: NEW(er) heads vs OLD heads

Wed Jan 25, 2012 12:48 pm

Rob in NH wrote:my 48 has a crack like that too, po brazed it and havnt had any problems with it.

Reguardless as to what you may have heard that is a freeze crack I have a stack of them like that

Re: NEW(er) heads vs OLD heads

Wed Jan 25, 2012 1:28 pm

Boss would probably know best but while you have the head off to be repaired or replaced I'd go ahead n check the block and head for warpage. To properly check you need a straight edge and feeler gauges. first check long wise, then 90 degrees to that then corner to corner making an X. This may sound like overkill but I've seen where all but one of the 5 different directions showed it fine but one would be warped. And if anyone is going to weld or braze the cracks I have a goood tip, first clean (so wife doesn't kill you lol) then heat the head slowly to 450-500 deg. (set @ 300 for 30 min n then 50 deg more per 30 min till you reach max oven temp. This will minimize warpage after welding/brazing. But check for warpage after welding to make sure it didn't , also if it needs welding and decking, do welding first so you don't have to re-deck the head after welding...

Re: NEW(er) heads vs OLD heads

Wed Jan 25, 2012 4:51 pm

it doesnt really matter how it was cracked but being cracked on the width if the head I wouldnt waste any time with it. I have seen many many cracked like that and almost always using magnaflux and black light will show the crack reaching almost the whole way through the head. get a good used head or a new one.

Re: NEW(er) heads vs OLD heads

Wed Jan 25, 2012 7:15 pm

I have a stack of cracked ones, not a stack of repaired ones big difference